Alternating fluorene‐di(thiophene)quinoxaline copolymers <i>via</i> microwave‐supported suzuki cross‐coupling reactions

Abstract

Abstract Three different acceptor moieties, 2,3‐di‐ n ‐octyl‐5,8‐ bis (5‐bromothiophene‐2‐yl)quinoxaline, 2,3‐ bis (4′‐ tert ‐butylbiphenyl‐4‐yl)‐5,8‐ bis (5‐bromothiophene‐2‐yl)quinoxaline, and 2,3‐ bis (4′‐ n ‐octylbiphenyl‐4‐yl)‐5,8‐ bis (5‐bromothiophene‐2‐yl)quinoxaline, have been designed und synthesized utilizing Suzuki cross‐couplings. Subsequently, these acceptor units have been connected to thiophene donor units by Stille cross‐couplings, resulting in three novel donor–acceptor–donor moieties. In addition, alternating copolymers of these donor–acceptor–donor building blocks with fluorene units have been prepared by microwave‐supported Suzuki cross‐couplings. The materials have been fully characterized and the optical properties have been analyzed. Single‐layer polymer red‐light‐emitting diodes have been prepared by blending 3 wt % of the alternating copolymers with poly(9,9′‐( bis ( n ‐octyl)fluorene‐ co ‐benzothiadiazole), revealing efficiencies ranging from 0.19 to 0.75 cd/A. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 7794–7808, 2008